There are many reasons why your eyes can be light sensitive. Sometimes it's an obvious cause like conjunctivitis. Other times it's not.
One of the most common reasons to experience glare in older people is cataracts. Initially you might find you are less comfortable driving at night than before and then when it gets worse, you might stop driving at night altogether. You may not twig that it is cataract because your daytime vision is actually OK.
Another common reason can be dry eye issues such as blepharitis. Dry eye results in the surface of your eye being irregular and this can cause light to scatter. Again you may not think immediately of dry eye as a cause, as maybe your eyes don't actually feel "dry".
The point is that if you suffer from light sensitivity or glare, it's worth going to see your optometrist or eye surgeon. There may be a fix... and you won't have to wear those sunglasses indoors anymore.
* Information on this blog is general in nature and should not be taken as professional medical advice or as a substitute for a consultation with a medical professional.